Anthracene dye.



ri sr sneer nests.

JOSEPH DEINET, or ELBERFELD, GERMANY, As'sIeNon TO FAEBENFABRIKEN VORM. FRIEDR. BAYER & 00., or ELBE'RFELD, GERMANY, A CORPORATION or GERMANY.

ANTHRACENE DYE Specification of Letters Patent.

Patented Dec. 24, 1907.

Application filed August 15. 1907. Serial No. 388643- T 0 all whom it may concern:

Be 1t known that I, J osnrn DEINET, citizen of the German Empire, residing at Elberfeld,

-Kingdom of Prussia, Germany, have invent- In carrying out my process practically I' can proceed as follows, the parts being by weight: A mixture of parts of anthraqinnone, 7 parts of powdered copper and 200 parts of sulfuric acid (66 Be), which mixture has to be continuously stirred, is slowly heat- 1 washed.

My new 'dyestuff is a black paste scarcely soluble in organic solvents. It dissolves in concentrated sulfuric acid with a dull brown color. Upon treatment with an alkaline solution oi l'iyi'lrosulfite of sodium, it yields a dull-violet vat which dyes unmordanted cotton brown fast shades. Other metals can be usedc. g. aluminium, silver etc.

Having now described my invention and in what nanner the same is to be performed, what I claim as new and desire to secure by Letters Patent, is z- The herein-described new dyestuff which can be obtained by treating a solution of anthraquinone in sulfuric acid with copper,

which dyestuii' is a black paste soluble in con-.

centrated sulfuric acid with a dull brown color, and giving a dull-violet vat with hydrosulfite and caustic soda lye, which vat stantially as hereinbefore described.

In testimony"whereof I have hereunto Set my hand in the presence of two subscribing witnesses.

JOSEPH DEINET. [Ls] Witnesses:

OTTO Ko'nie, VVALTER GREEFF.

dyes unmordanted cotton brown shades, sub- 

